Which email client for Linux?

I've been a thunderbird user since firefox was named firebird. I was happy with it, I like the way you can easily search over all accounts, how you can archive messages in folders by year by simply hitting the "a" key, I like the threads and even the "gmail" conversations extension even if I don't use it.

One problem with thunderbird is it became unusable when I added an old account which was accumulating mail up to over 170k messages. I know 170k messages is not realistic and no one should have so many messages in inbox but still this made me look for something better.

First let's see what I'm looking for in an email client:

Easy global search like thunderbird

Archive folders and 1 key hit like thudnerbird 🙂

Easy to mark messages as Spam/Junk with a single key hit, would be great to be able to mark multiple messages with a single key ( thunderbird doesn't have this )

Message threads

And last but not least, be able to handle a lot of messages in a folder, don't have to be super fast but at least it shouldn't lock

Here's what I tested so far:

Evolution

This was a nice surprise. Pro: Evolution downloaded 87k message headers in just a few seconds and had no problems with selecting all and moving around. Cons:

No archives

It has global search but it's a bit harder to access

Harder junk marking ( shift+ctrl+j instead of just j )

Always asks if I want to accept a certificate that's not issued for the exact domain of my email server ( at startup )

I could accept all the cons except for the lack of archiving. Anyone knows of a plugin that does archiving like thunderbird ? Please let me know!

Kmail

Becomes almost unusable with a big inbox ( 87k), hard to select all messages